Vedic Wisdom of today : Animal Killing (and eating) is a degraded activity in Kali Yuga.

 Animal Killing

The fourth degrading activity, and probably the most sensitive subject for most people in the West, is animal slaughter. This refers to slaughtering or troubling animal forms of life in order to eat their bodies or eggs. Implicated in this process are not only the actual killer of an animal but also the farmer, the transporter, the distributor, the retailer, and the server and eater of meat, fish and eggs.

When there is no other healthy food available, and where the land is unsuitable for cultivation for vegetable production and dairy farming (conditions generally found only in some desert areas and near the poles), a human being is justified in killing and eating animals. Otherwise, Vedic scriptures inform us that institutionalized animal slaughter and subsistence on animal flesh and eggs are the most condemned of all sinful activities, resulting in personal and social misery and effectively blocking any attempt at spiritual advancement.

Scriptural rules and regulations are not meant simply to inconvenience us in our attempt to enjoy life, but rather to open the door to higher and fuller enjoyment by spiritual realization in a peaceful culture. Please consider, therefore, the reasons offered by our line of spiritual masters to justify this Vedic injunction.

Reactions

The first reason is the reaction due to slaughter. In Bhagavad-gita it is explained that every action performed on the material platform—that is, with the intention to enjoy the result—will subject us to a reaction-in-kind in the future (generally in the next material body we take because of our material desires at the time of death). In other words, we will reap what we sow, as the Bible puts it, in terms of enjoyment and suffering in our next life, in exact accordance with the enjoyment or suffering we cause other living beings in this life.

Now, it is a cruel fact of life in the material world that one living being can feed himself only by troubling or killing another, and we all need to eat, even if we are culturing Krishna consciousness, simply to maintain our bodies. This does not, however, justify troubling or killing conscious animals who can experience fear and pain when systematically slaughtered. When milk products are available, as well as simpler forms of life that do not suffer when their fruit is removed or even when they are killed, such slaughter is completely unnecessary.

The cows, sheep and other animals we slaughter, as well as the chickens whose eggs we take, are all capable of consciously suffering, just as we do, because they have developed minds and senses. (Plants also, of course, can register rudimentary sensations, but nothing like the fear, pain and pleasure of animals.) Humans are more intelligent than animals, however, and if we misuse our intelligence simply to gratify our lusty tongues, causing misery to animals when we could instead subsist on simpler forms of life that do not suffer when killed, then, according to the Vedas, we ourselves will be liable to slaughter in the future. For example, today soldiers and civilians all over the world are being maimed and slaughtered in wars, just as they have previously slaughtered animals. The Vedas say that there will be constant wars as long as there are slaughterhouses, and in this way parents will have to suffer as their sons are killed, just as a cow suffers when her calf is dragged away and butchered to provide our veal cutlets. This is the law of karma (material activity).

Adverse Psychological Effects

The second reason for the Vedic injunction against meat eating is that eating of flesh (or unborn flesh—e.g., eggs) creates inauspicious psychological effects, especially for those who want to understand spiritual life. The animal food we eat has been dead for hours or days, usually by plan (as meat is aged to increase its flavor), and this means that it is decomposing. The harsh juices from such decomposing flesh cause corrosion in the nervous system, and this can ultimately result in senility, palsy or insanity. It is a verifiable fact that for those peoples of the world who are primarily vegetarian (such as the older generation in India) these three curses of life are much less common than in the West. On the other hand, the Vedas inform us that cows' milk provides us with necessary animal fat in a form just suitable for the development of the fine brain tissues and higher intelligence necessary for understanding spiritual life.

The more general psychological effect of eating animal foods is the creation of a gross state of consciousness in which one easily becomes harsh, angry and morose, and in which it is very difficult to understand the philosophy and practice of spiritual life The Vedas inform us that after many years of meat eating it is virtually impossible for a person to understand or accept spiritual principles, and even if he does understand, he cannot advance in the very subtle culture of spiritual knowledge and bliss until he puts aside this grossest habit. In addition to the Krishna consciousness movement, there are many groups interested in spiritual culture around the world who accept this principle of vegetarianism as essential, including some Christian sects and monastic orders and even some nondevotional sects such as the practicing Buddhists and impersonalists (monists) of Asia. Lord Buddha especially stressed the inauspicious psychological effects of flesh eating in preaching his doctrines of ahimsa (nonviolence) and meditation.

Source : https://krishna.com/four-enemies-spiritual-life